The uniform irradiation generated by beam self-focusing in the inhomogeneous atmosphere is studied. It is found that the uniform irradiation may appear on propagation of an initial flat-topped beam from the ground to space orbits because of the phase modulation caused by self-focusing in the inhomogeneous atmosphere. This may offer a way to achieve the uniform irradiation under the effect of inhomogeneous nonlinearity. The uniform irradiation on the target is interesting for the laser space-debris clearing. To achieve the uniform irradiation on the debris target, we present the fitting formula of the modified focal length, which presents an effective design rule for the uniform irradiation on the debris target. In addition, the influence of the beam order on the beam quality due to self-focusing is also investigated.